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Old 1st Aug 2014, 00:03
  #965 (permalink)  
FGD135
 
Join Date: Apr 2008
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tdracer, I would echo what TriStar_drvr and aterpster said about the likely reason for those 727 EIS crashes, which means that they were nothing like the 4 stall crashes we have had since 2009.


My point is that for the recent crashes, there was a period of airspeed decay, of which the pilots were unaware. This airspeed decay allowed the aircraft to stall, and it was this stall that was the primary reason for the crash. Oh, and the pilots were trying to fly the plane - they weren't gazing out the window.


I am of the belief that this tendency to be unaware of the airspeed decay is a recent development, and that the presentation of airspeed via the "tape" (as opposed to the big round dial of yesteryear) has got a lot to do with it.


If it can be shown that the industry did not experience similar accidents in the period prior to the glass cockpits than this would tend to support my assertion, hence my interest in this period. I thank those on this thread that are assisting me identify similar accidents from that period.


So far, only one has been identified that has the prerequisite period of airspeed decay, of which the pilots appear to have been unaware. This was identified by ironbutt57 and I thank him for that.


That accident was in 1972. It was a 737-200 that had levelled at the MDA, with speed brakes extended. It had just been instructed to go around, and that instruction was acknowledged. The stickshaker had been operating for a good 20 seconds, but the airspeed did not decay all the way to the stall, so it is possible the PF was aware of the airspeed. It was the retraction of the flap to 15 degrees that brought on the stall. The full report here:


http://libraryonline.erau.edu/online...s/AAR73-16.pdf
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